In this video, the host conducts a test of Windows Defender's efficacy against ransomware by executing a collection of the latest ransomware variants on a fully updated Windows system. This annual tradition aims to assess whether Windows Defender can effectively prevent ransomware from encrypting files. The host downloads the top 200 ransomware variants and executes them while observing the system's behavior and monitoring for any signs of encryption. Throughout the test, the host encounters notifications from Windows Defender about various threats being blocked, as well as instances where ransomware manages to bypass the security measures, ultimately leading to some files being encrypted. The experience highlights both the strengths and weaknesses of Windows Defender in real-time ransomware attacks, especially in dealing with newly emerging threats. The host reflects on the results and encourages viewers to share their thoughts on the outcome.